It originated in the 17th century, and while its most familiar application has probably been as a mechanical drawing instrument, it appears throughout engineering. 11-16 11 1, (2008) ISSN 1006-7290, pp. c, can make objects or forces move in the same direction, but at a set distance apart. Parallel Motion Linkage In a parallel motion linkage, as one end of the linkage is pulled or pushed, the other end of the linkage reacts in the same direction. •Parallel-Motion linkage, Fig. It was invented by the nineteenth-century mathematician Pafnuty Chebyshev, who studied theoretical problems in kinematic mechanisms. The linkage is connected to a support structure which guides its movement. 1, No. Parallel motion linkage used in a parallel arm fret saw. This linkage is comprised of three straight links, connected by two axle joints. engines was called the parallel motion linkage, a development of "Watt's linkage", but using the same principle. The industrial parallel-lift linkage allows Liebherr to offer both types of lift-arm kinematics on all of its models, from the L 514 with 12,520-lb. A parallel motion linkage is taught for the sliding keyboard cover of a piano to assure that the sliding keyboard cover, when shifted between its open (key exposing) position and its closed (key covering) position will remain perpendicular to the direction of its motion and will not skew or jam between the sides of the piano case. One of the problems was the construction of a linkage that converts a rotary motion into an This linkage is commonly used in suspension systems, as shown below. Watt's linkage (also known as the parallel linkage) is a type of mechanical linkage invented by James Watt (19 January 1736 25 August 1819) in which the central moving point of the linkage is constrained to travel on an approximation to a straight line. Watt's linkage consists of two long near-parallel links and a small floating link between them, with the near-linear motion occurring for a coupler point midway along the floating link. Technically classed as a four-bar linkage, it can be rotated through 360° without changing its function. A pantograph is a system of mechanical linkages which reproduces the motion of one point of the linkage at a second point, usually at an increased or decreased size. Optimization of Watt's Six-bar Linkage to Generate Straight and Parallel Leg Motion.pdf Journal of Humanoids, Vol. Linkages connected to two bell crank levers create a near vertical reciprocating sawing action. Linkages found in a sewing machine. The The piston of the engine is attached to the central point of the linkage, allowing it to act on the two outer beams of the linkage both by pushing and by pulling. The photograph above shows various linkages and levers in a typical sewing machine. The Chebyshev linkage is a mechanical linkage that converts rotational motion to approximate straight-line motion. This paper describes the procedure of optimal synthesis of a four-bar linkage, with the application of genetic algorithm and combination of cognates of the optimal mechanism to achieve a Watt's six-bar linkage.